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View Full Version : Let's play "You Pick the Power"



Frequency
02-28-2002, 06:44 PM
I'll be ordering a Cobalt 282. Vital statistics: 28'-8" long, 9' beam, 22 degree deadrise, 7750 lbs dry w/ twins. Clean straight vee hull with no hook. My choices for maximum power are Volvo 5.7GXi/SX, 5.7GXi/DP, 6.2L/Bravo 1, 6.2L Bravo 3. Best speed with B3 or DP drives is low 60's. The boat has not been tested with SX or B1 drives. Since I will want to flow exhaust through the outdrives at cruise from time to time, blowers may be out of the question.
Which package offers the best potential for top end without sacrificing agility and low end acceleration? Which package offers the best opportunity for minor mods to bump up horsepower? Opinions please!
Greg

Frequency
02-28-2002, 07:06 PM
[This message has been edited by Frequency (edited March 03, 2002).]

Magicfloat
02-28-2002, 07:10 PM
I would say definately DP or B3 drives Twin prop drives are the only way to go on that type boat.As far as Volvo or Merc,how is the local service situation in your area? Generally Mercs are easiier to get warranty and resale is better but if Volvo has a strong dealer presence where you are that's OK.As a general rule I recommend Merc but it can vary locally. The new 6.2's are great engines,on this size boat get as much HP as you can afford. My 2 cents

Frequency
02-28-2002, 07:19 PM
Cobalt's got me covered for 5 years on the powertrain, and I can get Volvo or Merc service where I boat. I don't want a hole-shot pig, but if I can gain 5 mph on the top by going with 6.2L / Bravo 1's it might be worth it. Maybe Bravo 1 props (4 blade) might make up for not having dual props? The Volvo 5.7GXi is just a Chevy 350, right. Can't I find 20 - 30 Hp without working too hard?? Questions, questions????

Magicfloat
02-28-2002, 07:26 PM
Do not go with Bravo 1's,serious mistake,go with Bravo 3's.As an example,Formula's 280SS,a simular size boat and simular market type, is only available with Bravo 3's or Duoprops.Twin props are the only way to go on this type of boat,and when you get ready to sell it or trade it,you'll know what I mean.

32fever
02-28-2002, 07:28 PM
WEll, if you can't go 900 sc with SSM VI's http://free.***boat.net/ubb/biggrin.gif http://free.***boat.net/ubb/biggrin.gif http://free.***boat.net/ubb/biggrin.gif http://free.***boat.net/ubb/biggrin.gif , my choice would be B3 with 6.2. I'd stay black, and I think Magicfloat is right. B3's are made for just this thing.
Not sure I'd wanna run my exhaust out the drive though at cruise...not very educated on that, but in my app, I don't want to do that at all, just use it at low rpm no wake zones only.
Mark

catnaround
03-01-2002, 04:24 AM
New Merc 525s! New Merc 525s!New Merc 525s!New Merc 525s!New Merc 525s!New Merc 525s!New Merc 525s!New Merc 525s!New Merc 525s!
Actaully I know nothing about the small blocks. Good luck with your choice and new boat

Magicfloat
03-01-2002, 05:21 AM
The new Merc 525's would be nice assuming you don't plan on boating this spring and summer.They will be quite late on availability.

Frequency
03-01-2002, 05:41 AM
Can't get big blocks! It would be nice if I could - a pair of HP500's would look good in the engine compartment! If I stick with dual props I'm tempted to go Volvo - keep hearing good things about that drive. According to Volvo's prop charts the DP props give impressive speeds when enough power is applied. I agree that Bravo 1's may be a problem on the low end, but that's with the standard 3 blade Mirage props. It seems no one has tried Bravo 1 props to see if the extra bite of 4 blades makes a difference. I'm not trying to build the Cobalt Poker Run Edition but I know Bravo 3's will kill top end and I sure would like to see the sweet side of 70 mph. Dreamin?
[This message has been edited by Frequency (edited March 01, 2002).]